Structural changes in the peptide backbone in complex formation between activated rhodopsin and transducin studied by FTIR spectroscopy.
Structural changes in the peptide backbone in complex formation between activated rhodopsin and transducin studied by FTIR spectroscopy.
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通过 FTIR 光谱研究活化视紫红质和转导蛋白之间形成复合物时肽主链的结构变化。
DOI：
10.1021/bi960911e
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发表时间：
1996
期刊：
影响因子：
2.9
通讯作者：
A. Maeda
中科院分区：
文献类型：
--
作者：
S. Nishimura;J. Sasaki;H. Kandori;T. Matsuda;Y. Fukada;A. Maeda
通过傅里叶变换红外光谱分析了视觉转导过程中转导蛋白和变视紫红质 II（光解视紫红质的活化形式）之间复合物形成的结构变化。复合物的光谱是通过减去变视紫红质 I 和未复合的变视紫质 II 的贡献而获得的。然后将复合物形成时的平均光谱与视紫质转化为变视紫红质II时的平均光谱进行比较。在变视紫红质 II 加转导蛋白形成复合物时，观察到肽羰基振动的频率从 1686、1674 和 1661 cm-1 移动到 1640 cm-1。这些变化一定是由一个或几个肽基团的氢键加强引起的，但不能归因于整体构象的变化。还检测到肽酰胺频率的变化。对于膜内羧酸残基，Asp83、Glu122 和 Glu113 的羧基振动没有发现进一步的变化。仅检测到可能由 Glu134 引起的微小变化。
Structural changes in the complex formation between transducin and metarhodopsin II, the activated form of photolyzed rhodopsin, in visual transduction processes were analyzed by Fourier transform infrared spectroscopy. The spectrum of the complex was obtained by subtracting the contribution of metarhodopsin I and uncomplexed metarhodopsin II. The averaged spectrum upon the complex formation was then compared with that in the conversion of rhodopsin-to-metarhodopsin II. Frequency shifts of the peptide carbonyl vibrations at 1686, 1674, and 1661 cm-1 to 1640 cm-1 were observed upon complex formation from metarhodopsin II plus transducin. These changes must have resulted from the strengthening of H-bonding of one or a few peptide groups but is not ascribable to global conformation change. Changes in the frequencies of the peptide amides were also detected. With regard to intramembrane carboxylic acid residues, no further changes were noticed in the carboxyl vibrations of Asp83, Glu122, and Glu113. Only a small change possibly due to Glu134 was detected.